Patients with gastroparesis often suffer with chronic gastrointestinal symptoms that are not adequately treated due to both a lack of understanding of the underlying pathophysiology and lack of effective treatments. The participation of Temple University in the NIH/NIDDK Gastroparesis Clinical Research Consortium and the proposed studies will help achieve the broad, long term objectives of improving the diagnosis and treatment of patients with gastroparesis. The PI and Temple University are exceptionally well qualified to continue to be one of the clinical centers in this consortium. Temple University has clinical expertise and an active research program in the evaluation and treatment of patients with gastroparesis. The aims for this renewal of the Gastroparesis Consortium are threefold. First, to complete the ongoing and approved studies initiated by the GpCRC. These studies include NORIG: a randomized trial of nortriptyline vs. placebo for idiopathic gastroparesis; GLUMIT-DG: a pilot study of safety, feasibility and potential efficacy of continuous glucose monitoring and insulin pump therapy in diabetic gastroparesis; APRON: a randomized trial of aprepitant vs. placebo for the relief of nausea in patients with chronic nausea and vomiting of presumed gastric origin; PBG: pathological basis of gastroparesis, a tissue study from full thickness gastric biopsies. Second, to maintain and expand the Gastroparesis Registry. Our aim is to have at least four years of follow-up on patients and with up to nine years for some patients. This will require maintenance of the Registry and continued periodic follow-up visits over the next five years. In addition, we propose recruitment of new patients during continuation of the Gastroparesis Consortium with refinements to existing questionnaires and pathophysiologic measures, as well as new ones. This will allow us to answer questions related to the pathogenesis, severity grading, complications, treatment responses, and clinical outcomes in patients with gastroparesis. Third, to conduct new multicenter studies of gastroparesis investigating the etiology, pathogenesis, diagnosis, and treatment. The PI with his collaborators at Temple University propose a multicenter study aimed at improving the diagnosis of gastric motility disorders. The overall purpose of this project is to develop a single more comprehensive noninvasive test which evaluates several components of gastric motility and, thus, may improve the correlation between dyspeptic symptoms and gastric dysmotility. This will ultimately enable physicians to better target therapy to the underlying gastric pathophysiologic abnormality in patients with gastroparesis.